The New Zealand Railways Magazine, Volume 7, Issue 1 (May 1, 1932.)
The Ant-Lion — The “Hideous”—the “Beautiful.”
THere is a well-known aphorism—“you cannot make a silk purse out of a sow's ear!” Such maxims may be applicable to mankind and his endeavours : not to wondrous Nature! She is a miracle worker who takes a hideous looking life-atom, puts it to sleep, waves her magic wand, and lo!—another life-atom of infinite and delicate beauty is evolved!
“Myrmeleon” is a Greek word that sounds euphoniously; translated into every-day English the phonetic resonance and charm vanishes, and “Ant-lion” remains to us!
Occasionally the “pit” or “trap” of “Myrmeleon” may be seen in sandy parts of our Islands. Mr. A. S. Atkinson writes: “These are not uncommon around Nelson.” However, the insect does not appear to be of widespread and frequent distribution through New Zealand, though more common in the North than South Island.
“Myrmeleon” belongs to the “Neuroptera,” which embraces also “Lace-wings” and “Caddis flies,” all of which are carnivorous during the larval period. Two of these may be briefly touched upon at present, viz:—
“Oxyethvia Albiceps”—the wonderful “Flask-insect”—unknown to any other part of the world; and “Chauliodes,” appearing from December to March, flying slowly over water, during the dusk, in large numbers. The larva of “Chauliodes” is not only carnivorous but cannibalistic; of violent and aggressive temperament, biting readily, and—considering its size—severely, if interfered with. These larvae lurk underneath stones in running streams, and devour enormous numbers of “Mayfly” larvae. The growth is slow, occupying twelve months; the chrysalid period embracing six to seven weeks, in an oval cell formed in the mud. The “perfect” insect retains its brown body, has pinkish-brown beautifully veined and marked guazy wings, with a spread of three inches.
Bearing a close relationship to “Neuroptera”—often so classified—are the “Dragon” and “Mayflies” of the order “Orthoptera.” The general observer may be easily forgiven for confusing these two orders, so very greatly are they similar in many respects.
“Orthoptera” embraces some of our largest and brightest insects; in fact, from the size and vivid colouration, one is reminded of tropical varieties, especially where “Dragonflies” are considered.
Our largest “Dragonfly”—uropetala—is quite common in all swamp lands during January and February, when it may be seen dashing about, preying on small insects, an object of dazzling beauty, resplendent in chocolate brown and gold, with gauzy opalescent wings. Two smaller and beautiful forms are “Lestes colensonis,” of irridescent metallic-blue, and “Telebasis Zealandica,” a burnished-crimson, darting flame. However, to return to “Myrmeleon!”
The larva of this insect is not at all “caterpillar” or “grub”-like; rather, it is more like a “perfect” insect in itself, and, no doubt, this peculiarity earned the name of “Ant-lion,” or “Myrmeleon.” As soon as the egg—laid in dry, loose sand—hatches out, the larva sets to work and constructs a “pit” or “trap,” shaped like an inverted cone. With an instinctive knowledge, the locality picked upon is near an “ant citadel,” or a distinct “antroute” for preference.page 61
Here again we are compelled to admire the design of Nature. The body of the larva is shaped to facilitate the “pit” formation; thick through centrally, and tapering to a point at each end; that which represents the head being armed with long, formidable, saw-toothed, boring mandibles. When shaping the pit, the insect whirls swiftly round and round till a suitable depth and circumference has been obtained; the larger sand-grains either butted or thrown clear of the rimedge. Now the “Ant-lion” ceases its labours, ambushes in the sand at the cone-point and awaits the coming of the “bill-of-fare.”
Presently, along comes a foraging ant, approaches the edge of the “pit” … it turns away and retreats … a premonition of lurking danger has been received! It returns, for ants are inquisitive … the phenomenon of the “pit” needs investigation …. it has reached the crumbling edge, and—death!
The ants approach has been telegraphed to “Myrmeleon” … hungry, waiting, alert for opportunity. The danger zone is reached … “Myrmeleon” sends up a veritable bombardment of sand molecules.
What is the object? Not, as may be thought, to disable or bring the prey down … not to confuse nor to terrify. What is it then? Let us watch and see!
With—shall we put it?—a scientific knowledge of engineering principles, this is being done to cut away the sand beneath the ant's foothold and produce a miniature landslide! The unfortunate victim to curiosity slithers down to inevitable doom … frantically it strives to recover foothold, to turn and flee … it is inexorably slipping down, down, down, a sand glissade!
A pair of long, horny, formidable mandibles flash upwards from the sand gulf … the prey seized and threshed violently into immobility …drawn within the cone centre … the ghoulish meal commenced! After the victim has been sucked dry, the empty chitin shell is thrown clear of the “pit,” and —“Myrmeleon,” the voracious, is again in ambush!
Now, it must not be thought the ant surrenders life tamely; they are courageous and pugnacious creatures … it puts up a strong fight, a fight to which there can be only one end! Savagely it attempts to bite in retaliation … to bring its spray of deadly formic acid into play … to use its sharp sting, if of that variety. There is no hope, the horny mandibles are impervious to bite, spray and sting alike, the vulnerable parts of “Myrmeleon” are not only remote but armoured in dry sand. The larva has one strange peculiarity; the legs are so placed to the trunk—the two longer front pairs forwards, the hind pair backwards—that the insect walks with a retrograde movement.
Our best known variety has been named “Myrmeleon Acutus” and strongly resembles the “Dragonfly” in slenderness of body—some forms are shorter and more squat bodied—and gauzy wing texture. Though of fairly graceful flight it has neither the “elan” nor dash of the other. Many insects diffuse a certain perfume; the “ghost-moth” that of pure apple, and so on. The perfume of “Myrmeleon” is of roses.
“Myrmeleon Acutus” has a wing expanse of from 2 1/2 inches in the “male” to 3 inches in the “female.” The body is grayish, lined in black; the head yellow, as are the legs, and that is also the predominant colour in the wing and other ornamentation. The antennae are absent, the body 1 1/4 inches in length. This insect—appears—as does our “Dragonfly,” uropetala—in January and February. It is seldom seen flying “free” during the day, more often specimens are obtained that have entered rooms, attracted by the glare of electric or other lights.
With France rests the distinction of possessing the largest and most beautiful variety, “Myrmeleon Libellulidae,” a boldly and splendidly marked object with a wing-spread of 4 1/2 inches and body over two inches long. The larva of “M.L.” does not form “pits” to snare its food, nor is it obliged to walk backwards.